It is narrated from Nafi' (may Allah be pleased with him) that it is narrated from Abdullah ibn Umar (may Allah be pleased with him) that he urinated in the market, then washed his face and hands, then wiped over his head, then entered the mosque. He was called for a funeral prayer, so he wiped over his leather socks and performed the funeral prayer. It is permissible to wipe over socks as well as leather socks.
Hadith Referenceمسند الإمام الشافعي / كتاب الطهارة / 82